1. Field of the Invention
The present invention relates to a method for the drying of the leather side of a furred animal pelt which is stretched out and fixed in this position on a pelt board, and a system for the execution of the method.
2. Description of Related Art
The invention further relates to a distension element/pelt board which can be used with the system, and which in the following will for practical reasons be randomly referred to as a pelt board or distension element, where said pelt board has a longitudinal axis, a first transverse axis (breadth axis) and a second transverse axis (height axis), and front end for receiving the cranium end of the pelt, and a foot end which terminates preferably at right-angles in relation to the longitudinal axis of the pelt board.
The invention also relates to a drying unit for use together with the pelt board.
In the drying of pelts, for example a mink or a fox pelt (in the following referred to jointly as a pelt), after skinning and scraping off the layer of fat on the leather side of the pelt, the pelts are stretched for example on a pelt board which is often first provided with a fat-absorbing material with the object that the remaining fat on the leather side of the pelt will be drawn into the paper and hereby removed from the pelt.
The use of pelt boards in connection with the drying of pelts is thus well-known, and with the passing of time there has been developed a great number of configurations of such pelt boards with the view of improving the drying of pelts.
With the mechanisation and organising of production and sale of pelts which has taken place, there has also occurred a certain standardisation of pelt sizes, and herewith also of the pelt boards on which the pelts are stretched and fixed in this position during the drying, the object being to be able to achieve the best possible and uniform pelt quality, which means that the producers can obtain a higher price for the pelts.
Those pelt boards which have become most widespread, and which today are used by the majority of the producers of pelts, including namely mink pelts, are made of wood, and can briefly be described as a flat piece of wood with a first broadside surface and a second broadside surface, and a first narrow side surface and a second narrow side surface, the breadth of which is essentially considerably less than the breadth of the broad side surface, and where the one end of the board (the foot end) is cut off at right-angles to the longitudinal axis of the board, and the lower end nearest the foot end has constant breadth, but hereafter this breadth gradually decreases towards a pointed but rounded end part (the front end, the nose end), and where the pelt board has a through-going slot between the first broadside surface and the second broadside surface, said slot lying symmetrically around the longitudinal axis of the board and extending between near the pointed end part and at least for over a half of the length of the board.
The pelt board described above is a pelt board intended for the pelts from male animals, which are normally larger than the pelts from female animals. A pelt board intended for use in the drying of the leather side of pelts from female animals does not comprise a lower end where the breath of the board is constant.
The following are some definitions which are intended to apply throughout the disclosure and claims:
The mounting of pelts is to be understood as a procedure which consists of the drawing of a pelt over a pelt board, preferably with the leather side of the pelt facing towards the surface of the board, the stretching of the pelt on the pelt board and the fastening/securing of the pelt in the stretched position on the pelt board.
The removal of the pelt from the pelt board, typically after the conclusion of the drying process, is to be understood as the removal of a pelt which has been stretched and fixed in this position on the board during the drying process. The procedure for removal also includes the removal of any elements which have been used for the fixing of the pelt in the stretched position on the pelt board.
In certain cases, the fat-absorbing material which is placed on the board before the drawing-on of the pelt consists of a bag made of fat-absorbing material, preferably of fat-absorbing paper with perforations, for example, in the form of a so-called “pelt bag,” which will thus be lying between the pelt board and the leather side of the pelt.
The drying procedure or drying of pelts shall be understood to be a drying-out of the leather side of the pelt to a preferred extent which from experience excludes the attack on the pelt by mites. The drying process is typically effected by the blowing of dry air in the slot in the board via pipes which are introduced into the slot, where via the perforations in the walls of the pelt bag the dry air is diffused out to the leather side of the pelt and dries the pelt.
In the drawing of the pelt on to the pelt board, a stretching of the pelt is often effected mechanically in order to achieve the greatest possible length of the pelts, and herewith the highest obtainable price at the fur auction. With more modern pelt board machines, a vibrating movement is imparted to the machine used for the stretching of the pelt, preferably arranged in the longitudinal axis of the pelt board, the result being that it becomes possible to stretch the pelts to a size category which is greater than that which can normally be achieved, this technique is disclosed in International Patent Application Publication WO 0244428 A1. The stretching of pelts following the method described leads to greater demands regarding the securing of the nose end of the pelt on the pointed end of the pelt board, and it is preferred that the pelt is secured in the stretched position during the drying in a manner which is non-destructive.
The method hitherto used to maintain the pelt in the stretched position on the pelt board during the consequent drying has consisted of fastening the pelt to the board with securing means, for example by staples or clips which are inserted manually and which penetrate the pelt. Use is made of 10-14 clips per pelt, which thus leave 20-28 holes in the dried pelt.
After drying, the clips are removed and thereafter the pelt is removed from the pelt board, which is also often effected mechanically, and which as a consequence of the maximum stretching of the pelt often leaves elongated holes in the pelt from the clips, the result being that the optimum price can not be achieved for the pelts at the fur auction, in that 2-3 cm of the pelt where this is broadest is ruined.
Sometimes, the mechanical removal of the clips also gives rise to damages to the pelts. The holes from the clips thus constitute great losses for the fur farmers, and furthermore considerably reduce the possibilities of use of the pelts when these are subsequently processed.
However, from International Patent Application Publication WO0162985 there is known a method and a bag-shaped holster, which in the following is referred to as a fixing-bag, for use in the securing of pelts stretched on a pelt board during the drying process. The fixing-bag, the shape of which corresponds substantially to the shape of a pelt board comprising a fat absorbing pelt bag over which a pelt is stretched, is drawn over the board with the stretched pelt from the cranium end of the pelt, so that the side of the fixing-bag facing the fur side of the pelt is in tight contact with the fur, which results in the pelt being pressed against the board with a force which is sufficient for the pelt to remain substantially in the stretched position during the drying. A further advantage with use of the fixing-bag is that a drying of the fur side of the pelt during the drying process is avoided, whereby the normal processing of the pelts with a water-bearing rotating brush, which results in a reduction of the fur's natural fat layer, and herewith the natural silky appearance of the pelt, can be omitted.
Considerable savings are thus achieved with the use of the fixing-bag, but the use of this demands that it is very correctly placed, and despite the placing being carried out correctly, it is ascertained that the stretched pelts secured on the pelt board by the fixing-bag slip slightly on each side of the tail root of the pelt, which can be due to the fact that sufficient holding force/friction can not be established between the surface of the pelt board and the leather side of the pelt on the broadside surfaces of the board, with reduced pelt size as a consequence. To counteract this, with a view to preserving the expected pelt size category, use is thus made of two to four staples which are driven through the pelt in the mentioned areas of slip and into the pelt board, as an extra security regarding the fixing of the pelt in the stretched position by the fixing-bag. The use of said staples will result in holes in the pelt in the stapled areas, thus reducing the value of the pelts, which is undesirable. Moreover, the use of the staples damages the wood of which the pelt board is made.
The work in connection with the dismounting (removal) of pelts stretched on pelt boards after the conclusion of the drying process is time-consuming, even though machines have been developed for the cutting-up of the fixing-bags, the extraction of the staples and the drawing-free of the pelt from the pelt board.
The use of the bag of fat-absorbing material, which is drawn over the pelt board so that this is placed between the wood and the leather side of the pelt, serves to protect the wooden board against the penetration of fat from the leather side of the pelt, which extends the lifetime of the pelt board and has the advantage that the pelt is easier loosened from the pelt board during its removal.
However, a disadvantage with the use of the pelt-bag is that it prevents the through-flow of air on the leather side of the pelt during the drying process, which can result in what is known in the fur trade as “black spots”, and herewith oxidisation of the leather side of the pelt. The said black spots are places on the pelt where the leather side has not been adequately dried during the drying process, and where the pelt is very exposed to attack from mites, with the result that the hairs on the fur side of the pelt become loose and can fall out, with consequently reduced possibilities of use for the pelt, which is completely undesirable. Moreover, pelts which have “black spots” can not be used in the production of fur products where the leather side of the pelt is turned outwards. It is estimated that 25% of the pelts received at the fur auctions can not be used with the leather side outwards because of insufficient drying. As a rule, said “black spots” arise in the places where the pelt is pressed against the surface of the pelt board with the greatest force, which most often will be the areas around the board's narrow sides where, as a result of the stretching of the pelt on the pelt board, the leather side of the pelt is drawn very tightly in against the board, which results in the drying in these areas being minimal. With the known pelt boards, operations are effected with two conflicting problems, namely the desire concerning the stretching of the pelts to the greatest possible size category, and the fastening of the pelt in this position during the drying without damaging the pelt, while at the same time being able to carry out an effective and uniform drying of the whole of the leather side of the pelt so that “black spots” are avoided.
Despite the improvements which have already been achieved with the use of fat absorbing pelt board bags and fixing bags for the fastening of the pelt stretched on the pelt board, there thus continues to exist a distinct need to solve the abovementioned recurring problems in connection with the drying of pelts, so that the pelts delivered to the fur auctions have a uniform quality.